NEW YORK — Royalty Pharma said Monday that it wants to buy Elan Corp. for about $6.5 billion, but has yet to receive a formal response from the Irish drug maker.
Royalty Pharma, a private company based in New York, said Monday that Elan hadn’t formally responded.
Elan released a statement questioning the timing of Royalty Pharma’s announcement, calling it ‘‘highly opportunistic,’’ but left the door open for future offers from Royalty Pharma or other suitors.
Elan noted that Royalty Pharma’s public announcement comes before shareholders can properly evaluate a pending deal. Elan has been a partner with Biogen Idec Inc. of Cambridge, Mass., on the drug Tysabri since 2000, but said earlier this month that it was ending that arrangement. As part of that deal, which is expected to close soon, Biogen will get full ownership of Tysabri and Elan will get a $3.25 billion payment, as well as royalties on all sales of the drug.